Reaction Types and Balancing Chemical Equations Review

The large number in front of a chemical formula or compound is the ___________.

• coefficient

• product

• physical

• chemical

How many atoms of aluminum are on each side of the following equation: 4Al + 3O₂ --> 2Al₂ O₃

• 2

• 6

• 1

• 4

Tags

NGSS.MS-PS1-1

NGSS.MS-PS1-5

Which equation is balanced?

• PbO₂ + 2H₂--> H₂SO₄

• SO₂ + H₂0 --> H₂SO₄

• 2Na + 2H₂O --> 2NaOH + H₂

• 2Na + 2H₂O --> 2NaOH + H

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The red numbers in the image below represent ________

• subscripts

• coefficients

• I don't know, and don't want to try

• None of the answers are correct

When balancing a chemical equation, you can only change _________, you can never change _______!

• coefficients, subscripts

• subscripts, coefficients

• formulas, subscripts

• coefficients, formula units

The blue numbers in the image below represent ________

• I don't know, and don't want to try

• coefficients

• subscripts

• none of the answers are correct

The substances at the beginning of a chemical equation are called the ____

• product

• yield

• chemical symbol

• reactants

In a chemical reaction, everything to the right of the arrow is called ______________.

• Products

• Yields

• Molecules

• Reactants

The number of atoms you begin with in a chemical reaction ...

• must be the same as the number of  atoms you end with

• must be an even number

• can be different to the number you finish with

• changes depending on how much energy is formed

Tags

NGSS.MS-PS1-5

Why must the number of atoms on either side of the arrow be equal to each other in a chemical equation?

• to abide by the law of conservation of energy

• to abide by law of conservation of mass

• to abide by the law of fundamental equations

• because everything must be even for the universe to stay in balance

Tags

NGSS.MS-PS1-5